The present invention relates to flush valves of the type commonly used to operate toilets and urinals and more specifically to an actuator which moves a valve handle in either a manual operation or an automatic operation. The flush valve may be a diaphragm-type valve, such as that sold by Sloan Valve Company of Franklin Park, Illinois, under the trademark ROYAL, and which is shown in U.S. Pat. No. 6,216,730, or it may be a piston-type of flush valve sold by Sloan Valve Company under the trademarks GEM and CROWN and shown for example in U.S. Pat. No. 5,881,993.
It is known to use an automatic actuator with a flush valve. Some devices of this type require that the standard manual valve handle be removed and replaced with some sort of electric or hydraulic motor. Such devices are inconvenient and expensive to install, especially if they are used to retrofit standard manual flush valves to automatic operation. Other automatic actuators allow the manual flush valve handle to be retained but the actuators are complicated to install as they require multiple parts or components that must be at least partially disassembled to permit them to be attached to the flush valve. Some automatic actuators provide for automatic operation only, which means if the automatic system becomes inoperative, the entire valve is useless until repairs can be made. Other actuators that do permit either automatic or manual operation are designed such that operation of one type interferes with the components involved in the other type. Battery life, sensor aiming and structural integrity are other areas of concern with prior art automatic actuators.